Process of making concrete pipe and tile.



No Drawing.

UNITED STATES PATENT OFFICE. 1

WILLIAM A. RnYnoLnS AND/BLAKE o. neurons; or ASHEVILLE, NORTH cniioni nii, ASSIG-NORSOF ONEHALF zro ram.- H. REYNOLDS, or AsHEvrLLR. No rnoA ornnm PROCESS or MAKING oolvonnrn PIPE AND TILE,

Siaecification 01' Letters Patent. 'P t flte Man g,:. 9 "A lication an my 19,1911. Serial No. 6 39.402.

Carolina, have invented new and useful Im-"' provements in the Process of Making Goncrete Pipeand Tile, of which the following is .a' specification.

Our invention relates to an improved process of making concrete pipe, tile and similar products from a mixture which includes crushed stone, sand and cement, and pertains more particularly to that part of the process relating to the setting and hardening of the admixture after molding.

The principalobjects of the invention are to provide a process which may be practiced wit-h great economy and which will. result in a product ofhetter quality than is now ,obtained by the working of such process for like purpo'ses'of which we have knowledge, and a'further object of our invention is to efl'ect a radical saving'in time for the pro duction of said articles in finished condition for use when made of said ingredients.

To these ends, our invention consists essentially of the process hereinafter described and more particularly pointed out in the claims.

In'working the process constituting our invention, a predetermined quantity of .crushed stone, ,sand or similar silicious ma- 'terial and Portland cement, comprising about two thirds of crushed stone and sand in the pre'ferred proportion to each other to make a compact mass, and onethird of cement, 'are thoroughly intermingled with ,suflicient moisture to produce suflicient consistency to form a bond to mold the mass in forms, but not enough to: prop-.

erly saturate and hydrate the mass to-e fiect the cohesion of the cement and otheringredients'. The semieplastic material thus prepared may now be molded in preferred forms forv pipe, tile 'or other articles, and" then conveyed into a steam and air-tight chamber, and the mold jackets removed. The steam chamber may be of any preferred design, the particular form of which comprises no part of this invention. The'steam chamber is then tightly sealedfand steam admitted thereto from any 'suitablesuppl'y at lowpressure of substantially less than one"lb.- Thev period of'indurjati'on at low five or six hours, during which the moisture in suspension and condensation permeates the pores of 'the molded forms and sets up the coheslve process of the cement... The

pressure of the steam is'then gradually increased to approximately one hundred pounds pressure at-vhich it is heldifor approximately four hours, which compacts the mass and completes the setting and hardening action of the mixture, after which the chamber may be opened and the products removed for cooling and use.

I In the manufacture of concrete products,

thus described, a more regular and uniform bond is accomplished, with greater hardness and strength, and the result is accomplished at a great economy of time and labor.

Havingthus described our invention, 'wha't we claim as new and desire Letters Patent, is-

1. The process of producing concrete pipe or tile from a composition including crushed stone, sand and cement, consistingv in incorto be secured by I porating and mixing the crushed stone, sand and cement,- adding suflicientflmoisture to partially hydrate the composition .and produce sufficientconsistency for molding sameinto forms without effecting the cohesion of the mass,;-molding same, then subjecting the molded composition to the action of steam in confinement under low pressure for a sufiicient peri-odto permit the moisture in suspension to permeate the pores of the molded forms and set up the cohesive process of thecement, and thereafter grad-- ually increasing the. degree of steam. pres;

'-sure to approximately .100 pounds "for a 'sufiicient period to compact the forms and complete the setting and hardening :action' of the composition, substantially as described.

2. The process of producing concrete pipeor tile from a composition including crushed stone, sand and cement, consisting in incorporating and mixing the crushed stone,sand and cement, adding sufficient moisture to partially hydrate the composition and produce suflicient consistency-,for molding same into forms, without efiecting the cohesion of themass, molding same, then subjectingthe molded composition to-the action of steam in confinement under approximately "one pound pressurefor substantially five or six hours; by which the moisture in suspension action of the composition, substantially as -perm'ea'tes the po'resof the molded forms described.

and sets up theeuhesive process of the ce- WILLIAMA. REYNOLDS. ment, and thereafter gradually increasing I BLAKE O. REYNOLDS.

5 the degree of steam pressure to a'pproximately 100' pounds for a period of-approxi- Witnesses: -mate1y four hours w11ich0ompaets the forms R. W. HAMMERSLOUGH,

and aompletes the setting 'and hardening t E. J. RANDOLPH. 

